package kr.hkit.powerjava.chapter16;

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;

import kr.hkit.powerjava.chapter14.work2.MyFrame;

class MyPanel extends JPanel implements ActionListener{
	boolean flag = false;
	private int light_number = 0;
	
	public MyPanel(){
		setLayout(new BorderLayout());
		JButton b= new JButton("traffic light turn on");
		b.addActionListener(this);
		add(b, BorderLayout.SOUTH);
	}
	
	@Override
	protected void paintComponent(Graphics g) {
		super.paintComponent(g);
		g.setColor(Color.BLACK);
		g.drawOval(100, 100, 100, 100);
		g.drawOval(100, 200, 100, 100);
		g.drawOval(100, 300, 100, 100);
		
		if(light_number ==0){
			g.setColor(Color.RED);
			g.fillOval(100, 100, 100, 100);
		}else if(light_number ==1){
			g.setColor(Color.YELLOW);
			g.fillOval(100, 200, 100, 100);
		}else{
			g.setColor(Color.GREEN);
			g.fillOval(100, 300, 100, 100);
		}
	}
	
	public void actionPerformed(ActionEvent e) {
		if(++light_number >= 3){
			light_number = 0;
		}
		repaint();
	}
}

public class TrafficLight extends JFrame {
	public TrafficLight(){
		add(new MyPanel());
		setSize(300, 500);
		setVisible(true);
	}
	
	public static void main(String[] args) {
		new TrafficLight();
	}
}
